Identify the inflection of the verb to climb. 1. infinitive 2. present, third person singular 3. past tense 4. participle

1. Infinitive tense is the verb in the 'to' form, so you got it right there: to climb.
2. Third person singular present tense is the present tense plus the letter 's' at the end because it is in third person.: climbs
3. Past tense is something that happened in the past: climbed
4. Participle is like the -ing form.: climbing

Hi !

to climb is infinitive 
"to" before a verb is the mark of the infinitive.

That's how it's  learned in foreign countries

hope  I helped

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